Electric-lamp socket



June 10, 1930. G. H. ELWELL ELECTRIC LAMP SOCKET Filed OCTl` l0, 1927NSULATIQN )INSULATION Patented `lune 10, 1930 UNITED STATES PATENToFFici:

GEORGE HENRY ELWELL, OF NEW HAVEN, CONNECTICUT, ASSIGNOR T0 THE GREISTMANUFACTURING COMPANY, A CORPORATION OF CONNECTICUT ELECTRIC-LAMP SOCKETApplication filed October 10, 1927. Serial No.` 225,191.

The invention relates to improvements in electric lamp sockets andespecially to the manner in which the screw-shell contact member issecured to the body of insulation. In the manufacture of the screw-shellcontact member it is customary to form it up into a cup shape and thento cut out a substantial portion of the bottom of the cup to provide anopen space for the center contact presented within the shell by theusualV washer of insulation lying between the screwshell and the body of insulation. Not only is the center opening t-hus providedin thescrew-shell contact for the reason stated, but the opening is usuallydiametrically enlarged by transverse extensions reaching entirely acrossthe bottom and extending a substantial distance into opposite portionsof the adjacent cylindrical wall of the shell. These extensions provideclearance for binding-posts in a 1nanner well-known to the art. Themetal bottom portion thus cut from the screw-shell becomes wastematerial and the shell is assembled to the body of insulation by meanssuch as screws extending axially through the body and washer ofinsulation and through a remaining portion of the screw-shell bottom toterminate in threaded bores in the anchorage of one of the bindingposts. It is therefore one of the objects of this invention to provide ascrew-shell contact having integral arms formed from the metalordinarily discarded as aforesaid, one of these arms providing abinding-post for the screw-shell contact while both of thearms providean important part of the assembling means of the shell to the body.Other objects will appear as the 1nvention is described.

The following is the description of an embodiment of the invention, theconstruction of which may be varied within the scope of what ishereinafter claimed, reference bein had tothe accompanying drawing (onesheet in which Figure 1 is an upright elevation of an improved lampsocket, the socket casing not being illustrated; Figure 2 is an uprightelevation of the same socket, but in a different rotary position; Figure3 is a cross-section at the dotted line Af-A in Figure 1; and the Figurel is a detail perspective view.

vided with axial grooves (not speciiically illustrated) in itscylindrical surface to accommodate the arms 2 and 3 throughout theirlength within the periphery of that body. lndentations 6 and 7presenting locking shoulders 8 and 9, respectively, are provided in theperiphery of the body 4 to accommodate the olf-set terminals 10 and 11of the arms, each of these terminals being provided with screw-holes toreceive, as illustrated by Figure 2, the screw l2 extending through thebody 4: as illustrated more par-` ticularly by dotted lines in Figures 1and 3, the threaded nut 13 permitting the tightening of the screw tobind the arms to the body with their oit-set terminals locked behindtheir respective shoulders. l/Vhen neither of the arms 2 and 3 are to beutilized as a binding post this screw 12 may be dispensed with, ifdesired;` for the off-set terminals 1() and 11 having snapped into theirrespective locking indentations 6 and 7 the screwfshell contact may besuiiiciently held thereby especially when the insulation lining (notillustrated) is made to fit snugly, as 1s customary, over that portionof the body 4C. The arm 2 being selected as the screw-shell bindingpost, an axially directed bore lll, as best illustrated by Figure 2, inthe body 4 provides a convenient passage from the capped end 15 of thesocket for the circuit wire (not illustrated) connective,` under thehead of the screw 12, to that arm. The body a is provided with a cavityto accomiriodate an electric switch of any adaptable type, and leadingfrom such cavity is a bore 16 extending axially farther into the bodyLl. A smaller bore 17 concentric with and continuous of the bore 16terminates with cowl an opening in the capped end 15 of the lamp socketaxis. A threaded and flanged sleeve 18 rests within bore 17 with itsflange within bore 16, a bent side extension 19 of the flange providedwith one of the contact points for circuit closing engagement by aswitch element, the other contact point being presented by a washer 5. Abinding-post screw 20 engages the threaded sleeve 18 and when tightenedtends to insure snug setting of the flange of the sleeve against theshouldered terminal of the bore 16, as illustrated in dotted line byFigure 1. It is obvious that, by

1 this improved method of assembling these parts of the lamp socket, theportion of metal ordinarily discarded is not only utilized, but certainparts ordinarily used in the construction of an electric lamp socket,suoli as the separate binding-post of the screw-shell contact andconnecting'parts are eliminated.

l/Vhat I claim is Y 1. An electric lamp socket comprisingin part, a bodyof insulation having indentations in its peripheral surface, eachindentation providing a shoulder, and a screw-shell having integralarms, each arm having an olf-set terminal for locking engagement with abody shoulder; 'l

2. An electric lamp socket comprising, in part, a body of insulationhaving indentations in its peripheral surface, each indentationproviding a shoulder and both indentations being connected by a boreextending through the body, a screw-shell contact having integral arms,each arm having a bored off-set terminal for locking engagement with abody shoulder, and a screw within the bores and. connecting the arms andheld by a threaded nut on the end of the screw, the screwhead providingmeans for binding a circuit wire to an arm of the screw-shell contact;

3. An electric lamp socket comprising, in part, a body of insulationhaving indentations in its peripheral surface, each indentationproviding a'shoulder; and a screw-shell contact having integral arms,each arm having an off-set terminal for locking engagement with a bodyshoulder, one of the arms forming a terminal for lthe screw-shellcontact;

4. An electric lamp socket comprising a body of insulation havingindentations in its peripheral surface, each'indentation providing ashoulder; a screw-shell Contact having arms, each arm having an off-setextremity for locking engagement with a body shoulder, one of the armsforming a terminal for the screw-shell contact; a washer of insulationlocked between the shell and the body; and a conductive member mountedupon the washer.

GEORGE HENRY ELWELL.

